This application claims the priority benefit of Taiwan application serial no.91207912,filed on May 13, 2002.
1. Field of Invention
The present invention relates to a non-volatile memory device. More particularly, the present invention relates to a non-volatile memory device having a built-in laser indicator.
2. Description of Related Art
Through the popularization of electronic products, the upkeep and maintenance of digital data has become part of our daily activities. To facilitate the transfer of data, manufacturers have developed portable storage devices that use non-volatile memory as the main storage medium. The non-volatile memory device is capable of connecting to a host machine through various types of external bus interfaces such as the universal serial bus (USB) interface, the RS232 interface or the 1394 interface. Since the memory device is easy to carry and easy to connect to a host system, non-volatile memory devices now have widespread use.
However, most non-volatile memory devices have data-recording capability only. Although simple data can be immediately obtained from the non-volatile memory device if a user needs to provide a brief report, other indication devices such as a laser emitter are often required to indicate the data being explained. Since a laser emitter needs power to generate a light beam and focus the light beam onto a small region, frequent use of the laser emitter demands frequent change of the battery. For a user who needs to use the portable memory device in long conferences, standby batteries or rechargeable batteries and a battery charger must be carried around at all times causing great inconvenience.
Accordingly, one object of the present invention is to provide a non-volatile memory device having a built-in laser indicator such that the laser indicator can be powered by an energy source within the non-volatile memory device.
To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention provides a non-volatile memory device with a built-in laser indicator. The device includes a connective port, a memory system, a power supply unit and a laser indicator. The connective port connects electrically with a host machine. The host machine passes data and provides power to the non-volatile memory device through an external bus on the connective port. The memory system holds data transmitted to the connective port temporarily before writing the data to the non-volatile memory device. The power supply unit is a storage device for electrical energy. When host power supplying the non-volatile memory device suddenly fails, the power supply unit provides back up power to write all received data into the non-volatile memory so that the data becomes readable. The laser indicator uses the power stored inside the power supply unit to produce light.
In one embodiment of this invention, the power supply unit also receives power from the host to charge up or regenerate the re-chargeable battery inside the power supply unit.
This invention also provides an alternative non-volatile memory device having a built-in laser indicator. The device includes a connective port, a buffer, a non-volatile memory, a memory controller, a battery and a laser indictor. The connective port connects electrically with a host machine. The host machine passes data and provides power to the non-volatile memory device through an external bus on the connective port. The buffer temporarily holds data transmitted to the connective port. The memory controller controls the transfer of data from the buffer to the non-volatile memory. The battery also receives power from the host. The laser indicator uses the power provided by the battery to produce light.
In one embodiment of this invention, the connective port has a configuration suitable for connecting with a universal serial bus (USB) interface, 1394 interface, RS232 interface, parallel transmission interface, personal computer multimedia card (PCMCIA) interface, flash memory card (CF) interface, secure digital memory card (SD) interface, multimedia memory card (MMC) interface or memory stick interface.
The non-volatile memory device not only has a built-in laser indicator, but also has a re-chargeable battery that can be charged during operation. Since a source of power is present to drive the laser indicator at all times, there is no need to carry extra batteries or to replace batteries from time to time.
In another embodiment of this invention, a detector may be installed to detect any variation in the power source. If power to the non-volatile memory device is cut off in the middle of a data writing operation, standby power may cut in to finish the writing operation. Furthermore, if power is suddenly lost in the middle of a file allocation table (FAT) update, the non-volatile memory device may use the standby power to finish the updating operation. Hence, stored data is rarely lost.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.